At the root of a discovery, there is often a minor event, perceived as unremarkable perhaps at the moment it occurs. In this case it was a visit by Robert Halleux to Greece, quite some time ago: “...I was visiting the massif of Laurium, and my guide pointed out an archaeological remnant, a piece of marble hidden by plants, the shape of a spiral, with a channel cut into it that looked like a crown of cups. I imagined some religious purpose. The guide set me straight, explaining that it was a helical panning device, in which ore washed over the stone by the water ended up being deposited in the little cups in decreasing order of the weight of its particles. This device for washing ores had been constructed by the ancients, although they had no notion of theoretical hydrodynamics. Over time, I realised that for millennia, artisans, the inventors of tools and processes, had created a tremendous amount of knowledge about the world of life. They were often well ahead of the scholars and scientists of their time. I wanted to learn about their knowledge and bring it closer to actual scientific knowledge, learning how it influenced science.

When techniques come before science

Today techniques follow science; technology is applied science. But this is a relatively recent state of affairs. For a very long time, it was the other way around! And no one seems to have noticed this, for a very good reason, according to Robert Halleux: in university departments, one is either a historian of techniques, or a historian of science, but never both. Historians of science work the way philosophers do: they study the development of scientific ideas. And they do this, most often, with little regard for the economic, political, technical or social context of the development. Normally no attention is paid to the conditions under which experiments were carried out. During his research, Prof. Halleux became aware that until the 17th century scientist-scholars like Aristotle or Galileo lagged in some ways behind the engineers and technicians.The great leaps forward in science, especially that which has been called the scientific revolution of the 17th century, were set in motion by changes in artisanal and industrial practice. One of the examples most often cited in support of this thesis involves mechanics (the study of movement), which was developed because of the creation of machines. Mechanisms were not constructed as a result of the study of principles of mechanics, but rather physicists attempted to understand why certain devices worked. Artillery officers were the ones who disproved Aristotle’s theory of movement...which was false. They already knew the truth that was indicated by Galileo’s experiment with falling bodies. They constructed a dynamics based on experiment and not on theoretical reasoning.